Stop mechanism for hoists or the like



Nov- 12, 1963 R. J. TEGTMEIER STOP MECHANISM FOR HOISTS OR THE LIKE 2 Sheets-Sheet 1 Filed Oct. 31 1961 ATTORNEK Nov. 12, 1963 R. J. TEGTMEIER STOP MECHANISM FOR HOISTS OR THE LIKE 2 Sheets-Sheet 2 Filed Oct. 31, 1961 ATTORNEY United States Patent 3,110,405 STU? MECHANISM FGR HOISTS OR THE LIKE Richard J. Tegtmeier, Weodside Road, Yardley, Pa. Filed Oct. 31, 1961, Ser. No. 143,884 8 Claims. (Cl. 214-1) This invention relates to an improved stop mechanism for limiting movement of a hoist or the like.

My stop mechanism is particularly useful in a metal strip processing line, such as an electrolytic tinning line or a continuous annealing line. Convent-ionally such lines are equipped with a collapsible coiling mandrel on which the strip coils at the exit end of the line, and a coil stripper for removing finished coils from the mandrel. Commonly the stripper includes a horizontally movable carriage, a drive for propelling the carriage, and a hoist supported on the carriage for lifting the coil after the mandrel is collapsed. The hoist has a vertically movable platform and a hydraulic mechanism for raising and lowering the platform. When the platform is raised to engage a coil on the mandrel from underneath, it must stop at the proper height or it may cause damage. The height at which the latform is to stop varies, since coil diameters vary. Previous stop mechanism for such hoists have been unduly cumbersome and not always reliable. Nevertheless it is apparent my invention may be used elsewhere for overcoming analogous problems.

An object of my invention is to provide a more reliable stop mechanism of simpler construction for use in coil strippers or the like.

A more specific object is to provide an improved stop mechanism which operates electrically on completion of a current path through a metal coil or other article as a hoist makes contact therewith.

In accomplishing these and other objects of the invention, I have provided improved details of structure, a preferred form of which is shown in the accompanying drawings, in which:

FIGURE 1 is a side elevational view with parts broken away of a coiling mandrel and stripper equipped with my stop mechanism;

FIGURE 2 is a vertical section on a larger scale on line III=I of FIGURE 1; and

FIGURE 3 is a schematic vn'ring diagram of the pertinent portion of the electric circuit.

FIGURE 1 shows a conventional power driven collapsible coiling mandrel 10, on which a coil C of strip metal winds at the exit end of a processing line, and a cooperating coil stripper 12, which removes finished coils from the mandrel. The stripper includes a horizontally movable carriage 13, rails 14 on which the carriage rides, a doubleacting horizontal hydraulic mechanism 15 for propelling the carriage, and sliding floor plates 16 fixed to opposite ends of the carriage. A hoist, which includes a vertically movable platform 17 of shallow V-shape in cross section and a double-acting vertical hydraulic mechanism 18 for raising and lowering the platform, is mounted on the carriage. The carriage can occupy a position at the left di rectly under the mandrel (shown in solid lines in FIG- URE 1) or a position at the right offset from the mandrel (shown in dot-dash lines in FIGURE 1). Since the foregoing parts are conventional, I have not shown them in any more detail.

In accordance with my invention, platform 17 has a recess 19 in its upper face intermediate its width and extending transversely to the V. Recess 19 has a horizontal bottom wall 20 and it houses a horizontal plate 21. A pair of vertical studs 22 depend from the underside of plate 21 and project through openings in the bottom wall 20 (FIGURE 2). Compression springs 23 encircle studs 22 and support plate 21 for vertical movement with respect to platform 17. Studs 22 carry jam nuts 22a which I use for making vertical adjustments to compensate for hydraulic drift inherent in the mechanism. Preferably plate 21 also carries depending guide pins 24 which project through bushings 25 in the bottom wall 20 to guide the plate in such movement. The upper face of plate 21 carries a box-like framework 26 of shallow V-shape in cross section. Respective contact bars 27 and 28 are fixed to the upper faces of this framework on opposite sides of the V, as with bolts 29 having countersunk heads. The upper faces of bars 27 and 28 lie in planes parallel with the upper faces of platform 17 above the platform. Longer electrically conductive bolts 36 and 31, also having countersunk heads, depend respectively from the undersides of bars 27 and 28 through enlarged openings in the bottom wall 20. Electric leads 32 and 33 are connected to the lower ends of the respective bolts and 31. The contact bars 27 and 28 and bolts 30 and 31 are electrically insulated from other parts of the mechanism. Sheets 34 of insulating material are interposed between the bars and framework 26; bushings 35 and 36 of insulating material material surrounding bolts 29 and bolts 30 and 3-1 respectively.

As FIGURE 3 shows, a solenoid 37 controls upward movement of platform 17 and the vertical hydraulic mechanism 18. This solenoid is connected across a suit able voltage source in series with a normally open car raise button 38 and normally closed contacts of a relay 39. The coil of relay 39 is connected across another suitable voltage source in series with a track limit switch 40, the electric lead 32, bolt 39, contact bars 27 and 28, bolt 31, and electric lead 33. As FIGURE 1 shows, switch 40 is mounted adjacent the path of movement of carriage 13, which carries an actuating arm 41 therefor. When the carriage moves to the left, arm 41 closes switch 40. When the carriage moves to the right, the arm opens the switch.

To strip a coil C from mandrel 10, I operate the horizontal hydraulic mechanism 15 to shift carriage 13 all the way to the left, thus closing switch 40, and I press the car raise button 38, thus energizing solenoid 37. The vertical hydraulic mechanism 18 lifts platform 17 until contact bars 27 and 28 engage coil C, whereupon a'current path is completed through the coil to energize relay 39. The relay picks up and opens its contacts, breaking the current path through solenoid 37. Because of the hydraulic drift in the mechanism, platform 17 continues to rise relative to the contact bars into lifting engagement with coil C. Thereafter I collapse the mandrel in the usual Way, and operate the horizontal hydraulic mechanism to shift carriage 13 to the right, thus stripping the coil from the mandrel and opening switch 41). Proper initial adjustment of jam nuts 22a assures that platform 17 comes to a stop with the eye of coil C concentric with the collapsed mandrel :for ease of stripping. I can now operate the vertical hydraulic mechanism 18 to raise or lower the coil as desired without interference from the stop mechanism. In the interest of conciseness, I have not shown the hydraulic circuit nor other parts of my electric circuit, such as those for operating the horizontal hydraulic mechanism 15 and operating the vertical hydraulic mechanism 18 downwardly, since they are not involved in the present invention.

From the foregoing description, it is seen that my invention affords a simple and reliable mechanism for stopping upward movement of a hoist or the like when it reaches a desired height. The mechanism avoids complicated mechanical parts, but instead relies on simple contacts for completing a current path through the article itself to initiate the stopping action.

While I have shown and described only a single em bodiment of my invention, it is apparent that modifications may arise. Therefore, I do not wish to be limited to the disclosure set forth but only by the scope of the appended claims.

I claim:

1. In a hoist which includes a platform and electrically controlled drive means for raising and lowering said platform, the combination therewith of a stop mechanism comprising a pair of electric contacts carried by said platform to engage an article as said drive means raises said platform into engagement therewith, and an electric circuit interconnecting said contacts and said drive means and completed through the article as the contacts engage the article for stopping operation of said drive means.

2. In a hoist which includes a platform and electrically controlled drive means for raising and lowering said platform, the combination therewith of a stop mechanism comprising a pair of electric contact bars movably mounted on said platform and electrically insulated therefrom, said contact bars being positioned to engage an article ahead of said platform as said drive means raises said platform into engagement with the article, and an electric circuit interconnecting said contact bars and said drive means and completed through the article as said contact bars engage the article for stopping operation of said drive means.

3. In a strip processing line which includes a coiling mandrel and a cooperating coil stripper, said stripper comprising a carriage movable horizontally to a first position directly under said mandrel and a second position offset from said mandrel, and a platform and electrically controlled drive means carried by said carriage for raising and lowering said platform, the combination therewith of a stop mechanism comprising electric contact means carried by said platform to engage a coil on said mandrel as said drive means raises said platform into engagement therewith, an electric circuit interconnecting said contact means and said drive means and completed through the coil when said carriage is in its first position and said contact means engage the coil for stopping operation of said drive means, and a limit switch connected in said circuit and operated by said carriage for breaking the circuit to said contact means when said carriage moves to its second position.

4. In a strip processing line which includes a coiling mandrel and a cooperating coil stripper, said stripper comprising a carriage movable horizontally to a first posi tion directly under said mandrel and a second position oifset from said mandrel, and a platform and electrically controlled drive means carried by said carriage for raising and lowering said platform, the combination therewith of a stop mechanism comprising a pair of electric contact bars movably mounted on said platform and electrically insulated therefrom, said contact bars being positioned to engage a coil on said mandrel ahead of said platform as said drive means raises said platform into engagement therewith, an electric circuit interconnecting said contact bars and said drive means and completed through the coil when said carriage is in its first position and said contact bars engage the coil for stopping operation of said drive means, and a limit switch connected in said circuit and operated by said carriage for breaking the circuit to said contact bars when said carriage moves to its second position.

5. In a strip processing line which includes a coiling mandrel and a cooperating coil stripper, said stripper comprising a carriage movable horizontally to a first position directly under said mandrel and a second position offset from said mandrel, and a V-shaped platform and an electrically controlled hydraulic mechanism carried by said vertical movement with respect to the platform, spring 7 means urging said contact bars to a position protruding above said platform, electric insulation between said contact bars and said platform, said contact bars being engageable with a coil on said mandrel as said hydraulic mechanism raises said platform into engagement therewith, an electric circuit interconnecting said contact bars and the control means for said hydraulic mechanism and completed through the coil when said carriage is in its first position and said contact bars engage the coil for stopping operation of said hydraulic mechanism, and a limit switch connected in said circuit and operated by said carriage for breaking the circuit to said contact bars when said carriage moves to its second position.

6. The combination, with a support adapted to be brought into engagement with an article and having a recess, and an electric circuit which controls operation of said support, of a stop mechanism comprising a framework housed in said recess, spring means urging said framework outwardly with respect to said support, a pair of contact bars carried by said framework and normally protruding from the face of said support for contacting an article ahead of the support, and means insulating said contact bars from said framework and said platform, said contact bars being connected in said circuit for opening the circuit as they make contact with the article.

7. The combination, with a platform adapted to be raised into contact with an article and having a transverse recess, and an electric circuit which controls the raising of said platform, of a stop mechanism comprising a framework housed in said recess, spring means urging said framework outwardly with respect to said platform, a pair of contact bars carried by said framework and normally protruding above said platform for contacting an article ahead of the platform, and means insulating said contact :bars from said framework and said platform, said contact ried by the upper face of said framework and lying in 7 planes parallel with the respective contacting faces of said platform and normally protruding above said platform for contacting an article ahead of the platform, bolts extending from the undersides of said contact bars through said framework for connection to electric leads, and means insulating said contact bars and said bolts from said framework and said platform, said contact bars being connected in said circuit for opening the circuit as they make contact with the article.

References Cited in the file of this patent UNITED STATES PATENTS 2,156,695 Klein May 2, 1939 2,198,644 Wettengel Apr. 30,1940 2,551,983 Wagner May 8, 1951 2,698,539 Gridel J an. 4, 1955 2,911,164 Caine Nov. 3, 1959 

1. IN A HOIST WHICH INCLUDES A PLATFORM AND ELECTRICALLY CONTROLLED DRIVE MEANS FOR RAISING AND LOWERING SAID PLATFORM, THE COMBINATION THEREWITH OF A STOP MECHANISM COMPRISING A PAIR OF ELECTRIC CONTACTS CARRIED BY SAID PLATFORM TO ENGAGE AN ARTICLE AS SAID DRIVE MEANS RAISES SAID PLATFORM INTO ENGAGEMENT THEREWITH, AND AN ELECTRIC CIRCUIT INTERCONNECTING SAID CONTACTS AND SAID DRIVE MEANS AND COMPLETED THROUGH THE ARTICLE AS THE CONTACTS ENGAGE THE ARTICLE FOR STOPPING OPERATION OF SAID DRIVE MEANS. 